<template>
  <div>
    <!-- 面包屑导航区域 -->
    <el-breadcrumb separator="/">
      <el-breadcrumb-item :to="{ path: '/home' }">首页</el-breadcrumb-item>
      <el-breadcrumb-item>商品管理</el-breadcrumb-item>
      <el-breadcrumb-item>参数列表</el-breadcrumb-item>
    </el-breadcrumb>

    <!-- 卡片视图区域 -->
    <el-card>
      <!-- 警告区域 -->
      <el-alert
        title="注意: 只允许为第三级分类设置相关参数!"
        type="warning" :closable="false"
        show-icon>
      </el-alert>

      <!-- 选择商品分类区域 -->
      <el-row :gutter="10" class="cat_opt">
        <el-col :span="6">
          <span>选择商品分类:</span>
          <!-- 选择商品分类的级联选择框 -->
          <el-cascader
          v-model="selectedCateKeys"
          :options="catelist"
          :props="cateProps"
          expandTrigger='hover'
          @change="handleChange"></el-cascader>
        </el-col>
      </el-row>

      <!-- tab 页签区域 -->
      <el-tabs v-model="activeName" @tab-click="handleTabClick">
        <!-- 添加动态参数的面板 -->
        <el-tab-pane label="动态参数" 
        name="many">
          <!-- 添加参数的按钮 -->
          <el-button type="primary"
          size='mini' :disabled="isBtnDisabled"
         @click="addDialogVisible = true">添加参数</el-button>
          <!-- 动态参数表格 -->
          <el-table :data="manyTableData" border stripe>
            <!-- 展开行 -->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <!-- 循环渲染Tag标签 -->
                <el-tag v-for="(item, index) in scope.row.attr_vals"
                :key="index" closable @close="handleClose(index,
                scope.row)">{{item}}</el-tag>
                <!-- 输入的文本框 -->
                <el-input
                class="input-new-tag"
                v-if="scope.row.inputVisible"
                v-model="scope.row.inputValue"
                ref="saveTagInput"
                size="small"
                @keyup.enter.native="handleInputConfirm(scope.row)"
                @blur="handleInputConfirm(scope.row)"
                >
                </el-input>
                <!-- 添加按钮 -->
                <el-button v-else class="button-new-tag" 
                size="small" @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column type="index"></el-table-column>
            <el-table-column label="参数名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button type="primary" icon="el-icon-edit"
                size="mini" @click="showEditDialog(scope.row.attr_id)">修改</el-button>
                <el-button type="danger" icon="el-icon-delete"
                size="mini" @click="removeParams(scope.row.attr_id)">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
        <!-- 添加静态属性的面板 -->
        <el-tab-pane label="静态属性" 
        name="only">
          <!-- 添加属性的按钮 -->
          <el-button type="primary"
          size='mini' :disabled="isBtnDisabled"
          @click="addDialogVisible = true">添加属性</el-button>
          <!-- 静态属性表格 -->
          <el-table :data="onlyTableData" border stripe>
            <!-- 展开行 -->
            <el-table-column type="expand">
              <template slot-scope="scope">
                <!-- 循环渲染Tag标签 -->
                <el-tag v-for="(item, index) in scope.row.attr_vals"
                :key="index" closable @close="handleClose(index,
                scope.row)">{{item}}</el-tag>
                <!-- 输入的文本框 -->
                <el-input
                class="input-new-tag"
                v-if="scope.row.inputVisible"
                v-model="scope.row.inputValue"
                ref="saveTagInput"
                size="small"
                @keyup.enter.native="handleInputConfirm(scope.row)"
                @blur="handleInputConfirm(scope.row)"
                >
                </el-input>
                <!-- 添加按钮 -->
                <el-button v-else class="button-new-tag" 
                size="small" @click="showInput(scope.row)">+ New Tag</el-button>
              </template>
            </el-table-column>
            <!-- 索引列 -->
            <el-table-column type="index"></el-table-column>
            <el-table-column label="属性名称" prop="attr_name"></el-table-column>
            <el-table-column label="操作">
              <template slot-scope="scope">
                <el-button type="primary" icon="el-icon-edit"
                size="mini" @click="showEditDialog(scope.row.attr_id)">修改</el-button>
                <el-button type="danger" icon="el-icon-delete"
                size="mini" @click="removeParams(scope.row.attr_id)">删除</el-button>
              </template>
            </el-table-column>
          </el-table>
        </el-tab-pane>
      </el-tabs>
    </el-card>

    <!-- 添加参数的对话框 -->
    <el-dialog
      :title="'添加' + titleText"
      :visible.sync="addDialogVisible"
      width="50%" @close="addDialogClosed">
      <!-- 添加参数的对话框 -->
      <el-form :model="addForm" :rules="addFormRules" 
      ref="addFormRef" label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="addForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="addDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="addParams">确 定</el-button>
      </span>
    </el-dialog>

    <!-- 修改参数的对话框 -->
    <el-dialog
      :title="'修改' + titleText"
      :visible.sync="editDialogVisible"
      width="50%" @close="editDialogClosed">
      <!-- 添加参数的对话框 -->
      <el-form :model="editForm" :rules="editFormRules" 
      ref="editFormRef" label-width="100px">
        <el-form-item :label="titleText" prop="attr_name">
          <el-input v-model="editForm.attr_name"></el-input>
        </el-form-item>
      </el-form>
      <span slot="footer" class="dialog-footer">
        <el-button @click="editDialogVisible = false">取 消</el-button>
        <el-button type="primary" @click="editParams">确 定</el-button>
      </span>
    </el-dialog>
  </div>
</template>

<script>
  export default{
    name: 'Params',
    data() {
      return {
        // 商品分类列表
        catelist: [],
        // 级联选择框的配置对象
        cateProps: {
          value: 'cat_id',
          label: 'cat_name',
          children: 'children'
        },
        // 级联选择框双向绑定到的数组
        selectedCateKeys: [],
        // 被激活的页签的名称
        activeName: 'many',
        // 这是动态参数的数据
        manyTableData: [],
        // 这是静态参数的数据
        onlyTableData: [],
        // 控制添加对话框的显示与隐藏
        addDialogVisible: false,
        // 添加参数的表单数据对象
        addForm: {
          attr_name: ''
        },
        // 添加表单的验证规则对象
        addFormRules: {
          attr_name: [
            { required: true, message: "请输入参数名称",
            trigger: "blur"},
            ]
        },
        // 控制修改对话框的显示与隐藏
        editDialogVisible: false,
        // 修改的表单数据对象
        editForm: {},
        // 修改表单的验证规则对象
        editFormRules: {
          attr_name: [
            { required: true, message: "请输入参数名称",
            trigger: "blur"},
            ]
        },
      }
    },
    created() {
      this.getCateList() 
    },
    methods: {
      // 获取所有的商品分类列表
      async getCateList() {
        const {data: res} = await this.$http.get('categories')
        if(res.meta.status !== 200) {
          return this.$message.error('获取商品分类失败!')
        }

        this.catelist = res.data

        console.log(this.catelist)
      },
      // 级联选择框选中项变化会触发这个函数
      handleChange() {
        this.getParamsData()
      },
      // tab页签点击事件的处理函数
      handleTabClick() {
        console.log(this.activeName)
        this.getParamsData()
      },
      // 获取参数的列表数据
      async getParamsData() {
        // 证明选中的不是三级分类
        if(this.selectedCateKeys.length !== 3) {
          this.selectedCateKeys = []
          this.manyTableData = []
          this.onlyTableData = []
          return 
        }

        // 证明选中的是三级分类
        console.log(this.selectedCateKeys)
        // 根据所选分类的Id和当前所处的面板,获取对应的参数
        const {data: res} = await this.$http.get
        (`categories/${this.cateId}/attributes`, 
        {params: {sel: this.activeName}})

        if(res.meta.status !== 200) {
          return this.$message.error('获取参数列表失败!')
        }

        console.log(res.data)
        res.data.forEach(item => {
          item.attr_vals = item.attr_vals ? 
          item.attr_vals.split(',') : []
          // 控制文本框的显示与隐藏
          item.inputVisible = false
          // 文本框中输入的值
          item.inputValue = ''
        })

        console.log(res.data)
        if(this.activeName === 'many') {
          this.manyTableData = res.data
        }else {
          this.onlyTableData = res.data
        }
      },
      // 监听添加对话框的事件
      addDialogClosed() {
        this.$refs.addFormRef.resetFields()
      },
      // 点击按钮,添加参数
      addParams() {
        this.$refs.addFormRef.validate(async valid => {
          if(!valid) return 
          const {data: res} = await this.$http.post
          (`categories/${this.cateId}/attributes`, {
            attr_name: this.addForm.attr_name,
            attr_sel: this.activeName
          })

          if(res.meta.status !== 201) {
            return this.$message.error('添加参数失败')
          }

          this.$message.success('添加参数成功!')
          this.addDialogVisible = false
          this.getParamsData()
        })
      },
      // 点击按钮,展示修改的对话框
      async showEditDialog(attr_id) {
        // 查询当前参数的信息
        const {data: res} = await this.$http.get
        (`categories/${this.cateId}/attributes/${attr_id}`,
        { params: { sattr_sel: this.activeName } })
        
        if(res.meta.status !== 200) {
          return this.$message.error('获取参数信息失败!')
        }
        this.editForm = res.data
        this.editDialogVisible = true
      },
      // 重置修改的表单
      editDialogClosed() {
        this.$refs.editFormRef.resetFields()
      },
      // 点击按钮,修改参数信息
      editParams() {
        this.$refs.editFormRef.validate(async valid => {
          if(!valid) return 
          const {data: res} = await this.$http.put
          (`categories/${this.cateId}/attributes/${this.editForm.attr_id}`,
          {attr_name: this.editForm.attr_name,
          attr_sel: this.activeName})

         if(res.meta.status !== 200) {
           return this.$message.error('修改参数失败!')
         } 

         this.$message.success('修改参数成功!')
         this.getParamsData()
         this.editDialogVisible = false
        })
      },
      // 根据Id删除对应的参数项
      async removeParams(attr_id) {
        const confirmResult = await 
        this.$confirm('此操作将永久删除该参数, 是否继续?', 
        '提示', {
          confirmButtonText: '确定',
          cancelButtonText: '取消',
          type: 'warning'
        }).catch(err => err)

        // 用户取消了删除的操作
        if(confirmResult !== 'confirm') {
          return this.$message.info('已取消删除!')
        }

        // 删除的业务逻辑
        const {data: res} = await this.$http.delete
        (`categories/${this.cateId}/attributes/${attr_id}`)

        if(res.meta.status !== 200) {
          return this.$message.error('删除参数失败!')
        }

        this.$message.success('删除参数成功!')
        this.getParamsData()
      },
      // 文本框失去焦点, 或按下了 enter 都会触发
      async handleInputConfirm(row) {
        if(row.inputValue.trim().length === 0) {
          row.inputValue = ''
          row.inputVisible = false
          return
        }
        // 如果没有return,则证明输入的内容需要进行后续处理
        row.attr_vals.push(row.inputValue.trim())
        row.inputValue = ''
        row.inputVisible = false; 
        // 需要发起请求,保存这次操作 
        this.saveAttrVals(row) 

      },
      // 将对 attr_vals的操作,保存到数据库
      async saveAttrVals(row) {
        // 需要发起请求,保存这次操作 
        const {data: res} = await this.$http.put
        (`categories/${this.cateId}/attributes/${row.attr_id}`,
        {
          attr_name: row.attr_name,
          attr_sel: row.attr_sel,
          attr_vals: row.attr_vals.join(',')
        })

        if(res.meta.status !== 200) {
          return this.$message.error('修改参数项失败!')
        }

        this.$message.success('修改参数项成功!')

      },
      // 点击按钮,展示文本输入框
      showInput(row) {
         row.inputVisible = true
        // 让文本框自动获得焦点
        // $nextTick 方法的作用,就是当页面上元素重新渲染之后,
        // 才会执行回调函数中的代码
        this.$nextTick(_ => {
          this.$refs.saveTagInput.$refs.input.focus();
        });
      },
      // 删除对应的参数可选项
      handleClose(index, row) {
        row.attr_vals.splice(index, 1)
        this.saveAttrVals(row)
      }
    },
    computed: {
      // 如果按钮需要被禁用,则返回true, 否则返回false
      isBtnDisabled() {
        if(this.selectedCateKeys.length !== 3) {
          return true
        }
        return false
      },
      // 这是当前选中的三级分类的Id
      cateId() {
        if(this.selectedCateKeys.length === 3) {
          return this.selectedCateKeys[2]
        }
        return null
      },
      // 动态计算标题的文本
      titleText() {
        if(this.activeName === 'many') {
          return '动态参数'
        }
        return '静态属性'
      }
    }
  }
</script>

<style lang="less" scoped>
.cat_opt {
  margin: 15px 0;
}

.el-tag {
  margin: 10px;
}

.input-new-tag {
  width: 120px; 
}
</style>
